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Your search keyword '"Ocker, Berthold"' showing total 7 results
Start Over Author "Ocker, Berthold" Journal applied physics letters
7 results on '"Ocker, Berthold"'

1. Spin–orbit torque driven multi-level switching in He+ irradiated W–CoFeB–MgO Hall bars with perpendicular anisotropy

Author

Zhao, Xiaoxuan, primary, Liu, Yang, additional, Zhu, Daoqian, additional, Sall, Mamour, additional, Zhang, Xueying, additional, Ma, Helin, additional, Langer, Jürgen, additional, Ocker, Berthold, additional, Jaiswal, Samridh, additional, Jakob, Gerhard, additional, Kläui, Mathias, additional, Zhao, Weisheng, additional, and Ravelosona, Dafiné, additional

Published
2020
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2. Enhancing domain wall velocity through interface intermixing in W-CoFeB-MgO films with perpendicular anisotropy

Author

Zhao, Xiaoxuan, primary, Zhang, Boyu, additional, Vernier, Nicolas, additional, Zhang, Xueying, additional, Sall, Mamour, additional, Xing, Tao, additional, Diez, Liza Herrera, additional, Hepburn, Carolyna, additional, Wang, Lin, additional, Durin, Gianfranco, additional, Casiraghi, Arianna, additional, Belmeguenai, Mohamed, additional, Roussigné, Yves, additional, Stashkevich, Andrei, additional, Chérif, Salim Mourad, additional, Langer, Jürgen, additional, Ocker, Berthold, additional, Jaiswal, Samridh, additional, Jakob, Gerhard, additional, Kläui, Mathias, additional, Zhao, Weisheng, additional, and Ravelosona, Dafiné, additional

Published
2019
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4. Assessment of conduction mechanisms through MgO ultrathin barriers in CoFeB/MgO/CoFeB perpendicular magnetic tunnel junctions.

Author

Silva, Ana V., Freitas, Paulo P., Lv, Hua, Fidalgo, Joao, Leitao, Diana C., Cardoso, Susana, Kampfe, Thomas, Riedel, Stefan, Langer, Juergen, Wrona, Jerzy, and Ocker, Berthold

Subjects
MAGNETIC tunnelling, RANDOM access memory, FIBERS, CURRENT-induced magnetization switching, ELECTRODES
Abstract

Perpendicular magnetic tunnel junctions (p-MTJs) have been explored for spin transfer torque magnetic random access memory devices (STT-MRAMs). The current-induced switching (CIS) of the p-MTJs requires a relatively high current density (J); thereby, very thin insulating barriers are required, consequently increasing the risk of non-tunneling conduction mechanisms through the MgO film. In this work, we fabricated CoFeB/MgO/CoFeB p-MTJs and studied the CIS characteristics, with the obtained switching current densities of about 2 × 1010 A/m2. The filament conduction through the MgO film was induced by applying a high set current (Iset) until a significant decrease in the resistance (R) is observed. A decrease in R with increasing current (I) for parallel (P) and antiparallel (AP) states was observed. In contrast, an increase in R with the increasing I value was observed for filament p-MTJs. We used a two-channel model to extract the filament resistance (Rf) and filament current (If). The Rf dependence on the electrical power (Pf) was linearly fitted, and a heating coefficient β of about 6%/mW was obtained, which was much higher than 0.15%/mW obtained from the bulk metallic multilayers of the top electrode. The CIS for filament p-MTJs was modeled by considering the bias dependence of the tunneling and the thermal dependence of Rf, showing a significant change in the CIS curves and switching currents. Our study addresses the effect of filament conduction on the tunneling current of CoFeB/MgO/CoFeB p-MTJs, critical for the design and control of the p-MTJ based devices, such as STT-MRAMs. [ABSTRACT FROM AUTHOR]

Published
2019
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5. Spin-orbit torques for current parallel and perpendicular to a domain wall

Author

Schulz, Tomek, primary, Alejos, Oscar, additional, Martinez, Eduardo, additional, Hals, Kjetil M. D., additional, Garcia, Karin, additional, Vila, Laurent, additional, Lee, Kyujoon, additional, Lo Conte, Roberto, additional, Karnad, Gurucharan V., additional, Moretti, Simone, additional, Ocker, Berthold, additional, Ravelosona, Dafiné, additional, Brataas, Arne, additional, and Kläui, Mathias, additional

Published
2015
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